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@@ -45,57 +45,418 @@ class TraceResolver;
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class TraceContext;
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/**
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* @brief Static routing protocol for IP version 4 stacks.
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*
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* In ns-3 we have the concept of a pluggable routing protocol. Routing
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* protocols are added to a list maintained by the Ipv4L3Protocol. Every
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* stack gets one routing protocol for free -- the Ipv4StaticRouting routing
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* protocol is added in the constructor of the Ipv4L3Protocol (this is the
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* piece of code that implements the functionality of the IP layer).
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*
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* The Ipv4StaticRouting class inherits from the abstract base class
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* Ipv4RoutingProtocol that defines the interface methods that a routing
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* protocol must support.
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*
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* When a packet arrives in the Ipv4L3Protocol for transmission, it comes
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* either from a local source via Ipv4L3Protocol::Send or from a remote
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* source via Ipv4L3Protocol::Forwarding. In both cases, a function is called
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* (Ipv4L3Protocol::Lookup) to look up the routing information for the packet.
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*
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* The lookup function iterates through the list of routing protocols asking
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* each to see if it can find a route and send the packet. A callback is
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* provided during each of these calls that should be considered a pre-
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* packaged send call. This is done to allow asynchronous calls into
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* routing subsystems in order to support on-demand routing, for example. The
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* method for requesting this operation is Ipv4StaticRouting::RequestRoute for
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* the static routing protocol.
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*
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* Each routing protocol is also free to implement its own methods for managing
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* routes which you will find below. This class manages a set of "static" or
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* manually configured routes for host, network and multicast routes.
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*
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* @see Ipv4RoutingProtocol
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* @see Ipv4L3Protocol::AddRoutingProtocol
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* @see Ipv4L3Protocol::Ipv4L3Protocol
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*/
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class Ipv4StaticRouting : public Ipv4RoutingProtocol
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{
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public:
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/**
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* @brief Construct an empty Ipv4StaticRouting routing protocol,
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* @internal
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*
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* The Ipv4StaticRouting class supports host, network and multicast routes.
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* This method initializes the lists containing these routes to empty.
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*
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* @see Ipv4StaticRouting
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*/
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Ipv4StaticRouting ();
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/**
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* @brief Request that a check for a route bw performed and if a route is found
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* that the packet be sent on its way using the pre-packaged send callback.
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*
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* The source and destination IP addresses for the packet in question are found
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* in the provided Ipv4Header. There are two major processing forks depending
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* on the type of destination address.
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*
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* If the destination address is unicast then the routing table is consulted
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* for a route to the destination and if it is found, the routeReply callback
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* is executed to send the packet (with the found route).
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*
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* If the destination address is a multicast, then the exact processing steps
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* depend on whether or not the packet has been sourced locally. This is
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* determined by the parameter ifIndex. This is the interface index over which
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* this packet was received. If the packet has not been received over a
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* network interface, this index will be set to
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* Ipv4RoutingProtocol::IF_INDEX_ANY (a very large number). In that case,
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* we want to avoid the requirement that an explicit route out of each node
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* must be set, so we don't do anything here.
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*
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* If the packet is a multicast destination and has been received over a
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* network interface, a call to this method implies that the packet is being
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* forwarded. In that case, there must be an explicit route out of the node.
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* A multicast route references the source address, the destination address
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* (the multicast group) and the input interface in order to find a route.
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* We consult the multicast routing table and, if a route is found, send the
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* packet out of as many interfaces as required using the provided callback
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* (think of it as a pre-packaged send call).
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*
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* @param ifIndex The network interface index over which the packed was
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* received. If the packet is from a local source, ifIndex will be set to
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* Ipv4RoutingProtocol::IF_INDEX_ANY.
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* @param ipHeader the Ipv4Header containing the source and destination IP
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* addresses for the packet.
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* @param packet The packet to be sent if a route is found.
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* @param routeReply A callback that packaged up the call to actually send the
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* packet.
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* @return Returns true if a route is found and the packet has been sent,
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* otherwise returns false indicating that the next routing protocol should
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* be consulted. In practice, the static routing protocol is the last chance
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* protocol.
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*
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* @see Ipv4StaticRouting
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* @see Ipv4RoutingProtocol
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*/
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virtual bool RequestRoute (uint32_t ifIndex,
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Ipv4Header const &ipHeader,
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Packet packet,
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RouteReplyCallback routeReply);
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/**
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* @brief Check to see if we can determine the interface index that will be
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* used if a packet is sent to this destination.
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*
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* This method addresses a problem in the IP stack where a destination address
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* must be present and checksummed into the IP header before the actual
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* interface over which the packet is sent can be determined. The answer is
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* to implement a known and intentional cross-layer violation. This is the
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* endpoint of a call chain that started up quite high in the stack (sockets)
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* and has found its way down to the Ipv4L3Protocol which is consulting the
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* routing protocols for what they would do if presented with a packet of the
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* given destination.
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*
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* Note that the a single interface index is returned. This means that if
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* the destination address is a multicast, and an explicit route is present
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* that includeds multiple output interfaces, that route cannot be used.
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*
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* If there are multiple paths out of the node, the resolution is performed
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* by Ipv4L3Protocol::GetIfIndexforDestination which has access to more
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* contextual information that is useful for making a determination.
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*
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* @param destination The Ipv4Address if the destination of a hypothetical
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* packet. This may be a multicast group address.
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* @param ifIndex A reference to the interface index over which a packet
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* sent to this destination would be sent.
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* @return Returns true if a route is found to the destination that involves
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* a single output interface index, otherwise returns false indicating that
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* the next routing protocol should be consulted. In practice, the static
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* routing protocol is the last chance protocol.
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*
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* @see Ipv4StaticRouting
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* @see Ipv4RoutingProtocol
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* @see Ipv4L3Protocol
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*/
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virtual bool RequestIfIndex (Ipv4Address destination, uint32_t& ifIndex);
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/**
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* @brief Add a host route to the static routing table.
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*
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* @param dest The Ipv4Address destination for this route.
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* @param nextHop The Ipv4Address of the next hop in the route.
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* @param interface The network interface index used to send packets to the
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* destination.
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*
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* @see Ipv4Address
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*/
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void AddHostRouteTo (Ipv4Address dest,
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Ipv4Address nextHop,
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uint32_t interface);
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/**
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* @brief Add a host route to the static routing table.
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*
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* @param dest The Ipv4Address destination for this route.
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* @param interface The network interface index used to send packets to the
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* destination.
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*
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* @see Ipv4Address
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*/
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void AddHostRouteTo (Ipv4Address dest,
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uint32_t interface);
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/**
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* @brief Add a network route to the static routing table.
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*
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* @param network The Ipv4Address network for this route.
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* @param networkmask The Ipv4Mask to extract the network.
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* @param nextHop The next hop in the route to the destination network.
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* @param interface The network interface index used to send packets to the
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* destination.
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*
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* @see Ipv4Address
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*/
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void AddNetworkRouteTo (Ipv4Address network,
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Ipv4Mask networkMask,
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Ipv4Address nextHop,
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uint32_t interface);
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/**
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* @brief Add a network route to the static routing table.
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*
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* @param network The Ipv4Address network for this route.
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* @param networkmask The Ipv4Mask to extract the network.
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* @param interface The network interface index used to send packets to the
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* destination.
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*
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* @see Ipv4Address
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*/
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void AddNetworkRouteTo (Ipv4Address network,
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Ipv4Mask networkMask,
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uint32_t interface);
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/**
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* @brief Add a default route to the static routing table.
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*
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* This method tells the routing system what to do in the case where a specific
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* route to a destination is not found. The system forwards packets to the
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* specified node in the hope that it knows better how to route the packet.
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*
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* If the default route is set, it is returned as the selected route from
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* LookupStatic irrespective of destination address if no specific route is
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* found.
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*
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* @param nextHop The Ipv4Address to send packets to in the hope that they
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* will be forwarded correctly.
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* @param interface The network interface index used to send packets.
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*
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* @see Ipv4Address
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* @see Ipv4StaticRouting::Lookup
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*/
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void SetDefaultRoute (Ipv4Address nextHop,
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uint32_t interface);
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/**
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* @brief Get the number of individual unicast routes that have been added
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* to the routing table.
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*
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* @warning The default route counts as one of the routes.
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*/
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uint32_t GetNRoutes (void);
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/**
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* @brief Get the default route from the static routing table.
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*
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* @return If the default route is set, a pointer to that Ipv4Route is
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* returned, otherwise a zero pointer is returned.
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*
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* @see Ipv4Route
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*/
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Ipv4Route *GetDefaultRoute (void);
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/**
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* @brief Get a route from the static unicast routing table.
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*
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* Externally, the unicast static routing table appears simply as a table with
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* n entries. The one sublety of note is that if a default route has been set
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* it will appear as the zeroth entry in the table. This means that if you
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* add only a default route, the table will have one entry that can be accessed
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* either by explicity calling GetDefaultRoute () or by calling GetRoute (0).
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*
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* Similarly, if the default route has been set, calling RemoveRoute (0) will
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* remove the default route.
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*
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* @param i The index (into the routing table) of the route to retrieve. If
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* the default route has been set, it will occupy index zero.
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* @return If route is set, a pointer to that Ipv4Route is returned, otherwise
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* a zero pointer is returned.
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*
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* @see Ipv4Route
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* @see Ipv4StaticRouting::RemoveRoute
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*/
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Ipv4Route *GetRoute (uint32_t i);
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/**
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* @brief Remove a route from the static unicast routing table.
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*
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* Externally, the unicast static routing table appears simply as a table with
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* n entries. The one sublety of note is that if a default route has been set
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* it will appear as the zeroth entry in the table. This means that if the
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* default route has been set, calling RemoveRoute (0) will remove the
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* default route.
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*
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* @param i The index (into the routing table) of the route to remove. If
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* the default route has been set, it will occupy index zero.
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*
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* @see Ipv4Route
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* @see Ipv4StaticRouting::GetRoute
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* @see Ipv4StaticRouting::AddRoute
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*/
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void RemoveRoute (uint32_t i);
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/**
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* @brief Add a multicast route to the static routing table.
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*
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* A multicast route must specify an origin IP address -- the address of the
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* node that originates packets destined for a given multicast group. This
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* address may be Ipv4Address::GetAny (typically 0.0.0.0) if the multicast
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* group is open, or it may specify a single IP address if the multicast
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* group is closed. The route must also specify the multicast group address.
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*
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* For each route, the input nework interface must be specified. For
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* forwarding operations, this is the interface index that you expect multicast
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* packets to arrive over. If you want to specify routes off of a local node
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* for given multicast groups, this index may be set to
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* Ipv4RoutingProtocol::IF_INDEX_ANY.
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*
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* For each route, a vector of output network interfaces must also be
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* specified. When the RequestRoute operation is performed, copies of a
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* packet are sent out all of the specified interfaces.
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*
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* @param origin The Ipv4Address of the origin of packets for this route. May
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* be Ipv4Address:GetAny for open groups.
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* @param group The Ipv4Address of the multicast group or this route.
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* @param inputInterface The input network interface index over which to
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* expect packets destined for this route. May be
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* Ipv4RoutingProtocol::IF_INDEX_ANY for packets of local origin.
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* @param outputInterface A vector of network interface indices used to specify
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* how to send packets to the destination(s).
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*
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* @see Ipv4Address
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*/
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void AddMulticastRoute (Ipv4Address origin,
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Ipv4Address group,
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uint32_t inputInterface,
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std::vector<uint32_t> outputInterfaces);
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void SetDefaultMulticastRoute (Ipv4Address origin,
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Ipv4Address group,
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uint32_t inputInterface,
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std::vector<uint32_t> outputInterfaces);
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/**
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* @brief Add a default multicast route to the static routing table.
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*
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* This is the multicast equivalent of the unicast version SetDefaultRoute.
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* We tell the routing system what to do in the case where a specific route
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* to a destination multicast group is not found. The system forwards
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* packets out the specified interface in the hope that "something out there"
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* knows better how to route the packet.
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*
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* Since we're basically forwarding packets to some entity we think may know
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* better what to do, we don't pay attention to subleties like origin address
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* and input interface, nor do we worry about forwarding out multiple
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* interfaces. If the default multicast route is set, it is returned as the
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* selected route from LookupStatic irrespective of origin, multicast group or
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* input interface if another specific route is not found.
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*
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* @param outputInterface The network interface index used to specify where
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* to send packets in the case of unknown routes.
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*
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* @see Ipv4Address
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*/
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void SetDefaultMulticastRoute (uint32_t outputInterface);
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/**
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* @brief Get the number of individual multicast routes that have been added
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* to the routing table.
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*
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* @warning The default multicast route counts as one of the routes.
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*/
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uint32_t GetNMulticastRoutes (void) const;
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/**
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* @brief Get a route from the static multicast routing table.
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*
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* Externally, the multicast static routing table appears simply as a table
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* with n entries. The one sublety of note is that if a default route has
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* been set it will appear as the zeroth entry in the table. This means that
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* if you add only a default route, the table will have one entry that can be
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* accessed either by explicity calling GetDefaultMulticastRoute () or by
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* calling GetMulticastRoute (0).
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*
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* Similarly, if the default route has been set, calling
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* RemoveMulticastRoute (0) will remove the default route.
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*
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* @param i The index (into the routing table) of the multicast route to
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* retrieve. If the default route has been set, it will occupy index zero.
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* @return If route <i> is set, a pointer to that Ipv4MulticastRoute is
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* returned, otherwise a zero pointer is returned.
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*
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* @see Ipv4MulticastRoute
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* @see Ipv4StaticRouting::RemoveRoute
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*/
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Ipv4MulticastRoute *GetMulticastRoute (uint32_t i) const;
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/**
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* @brief Get the default multicast route from the static routing table.
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*
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* @return If the default route is set, a pointer to that Ipv4MulticastRoute is
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* returned, otherwise a zero pointer is returned.
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*
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* @see Ipv4Route
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*/
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Ipv4MulticastRoute *GetDefaultMulticastRoute (void) const;
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void RemoveMulticastRoute (Ipv4Address origin,
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/**
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* @brief Remove a route from the static multicast routing table.
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*
|
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|
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|
* Externally, the multicast static routing table appears simply as a table
|
|
|
|
|
* with n entries. The one sublety of note is that if a default multicast
|
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|
|
|
* route has been set it will appear as the zeroth entry in the table. This
|
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* means that the default route may be removed by calling this method with
|
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|
* appropriate wildcard parameters.
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*
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* This method causes the multicast routing table to be searched for the first
|
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|
* route that matches the parameters and removes it.
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|
*
|
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|
* @param origin The IP address specified as the origin of packets for the
|
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|
* route.
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|
* @param origin The IP address specified as the multicast group addres of
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|
* the route.
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|
* @param inputInterfade The network interface index specified as the expected
|
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|
|
* input interface for the route.
|
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|
|
* @returns True if a route was found and removed, false otherwise.
|
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|
|
*
|
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|
|
|
* @see Ipv4Route
|
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|
|
|
* @see Ipv4StaticRouting::GetRoute
|
|
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|
|
* @see Ipv4StaticRouting::AddRoute
|
|
|
|
|
*/
|
|
|
|
|
bool RemoveMulticastRoute (Ipv4Address origin,
|
|
|
|
|
Ipv4Address group,
|
|
|
|
|
uint32_t inputInterface);
|
|
|
|
|
|
|
|
|
|
/**
|
|
|
|
|
* @brief Remove a route from the static multicast routing table.
|
|
|
|
|
*
|
|
|
|
|
* Externally, the multicast static routing table appears simply as a table
|
|
|
|
|
* with n entries. The one sublety of note is that if a default multicast
|
|
|
|
|
* route has been set it will appear as the zeroth entry in the table. This
|
|
|
|
|
* means that if the default route has been set, calling
|
|
|
|
|
* RemoveMulticastRoute (0) will remove the default route.
|
|
|
|
|
*
|
|
|
|
|
* @param index The index (into the multicast routing table) of the route to
|
|
|
|
|
* remove. If the default route has been set, it will occupy index zero.
|
|
|
|
|
*
|
|
|
|
|
* @see Ipv4Route
|
|
|
|
|
* @see Ipv4StaticRouting::GetRoute
|
|
|
|
|
* @see Ipv4StaticRouting::AddRoute
|
|
|
|
|
*/
|
|
|
|
|
void RemoveMulticastRoute (uint32_t index);
|
|
|
|
|
|
|
|
|
|
protected:
|
|
|
|
|
|